Cited 9 time in webofscience Cited 7 time in scopus

Optical properties of the iron-based superconductor LiFeAs single crystal

Optical properties of the iron-based superconductor LiFeAs single crystal
Min, BH[Min, Byeong Hun]Hong, JB[Hong, Jong Beom]Yun, JH[Yun, Jae Hyun]Iizuka, T[Iizuka, Takuya]Kimura, S[Kimura, Shin-ichi]Bang, Y[Bang, Yunkyu]Kwon, YS[Kwon, Yong Seung]
DGIST Authors
Min, BH[Min, Byeong Hun]; Kwon, YS[Kwon, Yong Seung]
Issue Date
New Journal of Physics, 15
Article Type
Dielectric FunctionsHigh Temperature SuperconductorsInter-Band TransitionIron-Based SuperconductorsLow-Temperature DataMetallic BehaviorsOptical ConductivityOptical Conductivity SpectraPlasma FrequenciesReflectivity SpectraSemiconductor Quantum WellsSingle CrystalsSuperconductivity
We have measured the reflectivity spectra of the LiFeAs (Tc = 17.6 K) single crystal in the temperature range from 4 to 300 K. In the superconducting (SC) state (T < Tc), the clean opening of the optical absorption gap was observed below 25 cm-1, indicating an isotropic full gap formation. In the normal state (T > Tc), the optical conductivity spectra display typical metallic behavior with the Drude-type spectra at low frequencies, but we found that the introduction of the two Drude components best fits the data, indicating the multiband nature of this compound. A theoretical analysis of the low-temperature data (T = 4 K < Tc) also suggests that two SC gaps best fit the data and their values were estimated as Δ1 = 3.3 meV and Δ2 = 1.59 meV, respectively. Using the Ferrell-Glover-Tinkham sum rule and dielectric function 1 (ω), the plasma frequency of the SC condensate (ωps) is consistently estimated to be 6665 cm-1, implying that about 65% of the free carriers of the normal state condense into the SC condensate. To investigate the various interband transition processes (for ω > 200 cm-1), we have also performed the local-density approximation band calculation and calculated the optical spectra of the interband transitions. This theoretical result provided qualitative agreement with the experimental data below 4000 cm-1 . © IOP Publishing and Deutsche Physikalische Gesellschaft.
Institute of Physics Publishing
Related Researcher
  • Author Kwon, Yong Seung Quantum Functional Materials Laboratory
  • Research Interests High Tc Superconductors and magnetic materials; Thermoelectric Materials
There are no files associated with this item.
Emerging Materials ScienceQuantum Functional Materials Laboratory1. Journal Articles

qrcode mendeley

Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.